Sepsis, severe sepsis, and septic shock represent a serious medicinal and general social problem and still maintain an important position among the present issues in the basic and clinical research. In the prospective analysis of patients satisfying the criteria of septic condition, we determined serum levels of bioparameters in three consecutive days from the first signs of sepsis depending on the stage or advancement of the septic condition. We determined the most significant parameter/parameters which are able to determine the stage of sepsis or to predict patient's death. In the group of 68 patients, all monitored biomarkers showed significant difference in serum concentrations versus the control group (P = 0.001). The strongest positive connection between the seriousness of sepsis and serum level is in case of procalcitonin. Predictor of mortality (r = -0.468; P = 0.001), transferrin (r = -0.506; P = 0.003), and tumor necrosis factor-α (r = 0.939; P = 0.001). Our results show that the monitored parameters (procalcitonin, C-reactive protein, tumor necrosis factor-α, and interleukin 6) have strong correlations between the serum levels and the stage of disease. Examination of at least one cytokine in normal clinical practice might lead to better interpretation of the patient's condition, determining the risk of death.